1. Field of the Invention
The present invention relates to emergency signal transmitters for the purpose of summoning medical aid in the event of a medical emergency, such as in remote areas. In particular, the present invention relates to a wristmounted vital functions monitor for automatically detecting a medical emergency situation and generating the required emergency radio signal.
2. Description of the Prior Art
Emergency locator radio transmitters are commonly used in airplanes to generate a radio signal to assist search and rescue teams in locating an airplane in the event of a crash. Similar emergency locators have been developed for personal use, which locators can be actuated by the individual, such as a hunter or fisherman, in the event that the individual becomes lost. Examples of such personal locators are disclosed in U.S. Pat. No. 3,806,936 issued Apr. 23, 1974 to Aero Electronics Development Co. and in U.S. Pat. No. 4,121,160 issued Oct. 17, 1978 to Cataldo. Such emergency locators require, however, that the individual be sufficiently healthy and lucid to appreciate his predicament and activate the device.
Systems are also known for the remote monitoring of the vital functions of hospital patients whereby such vital functions as pulse rate and body temperature are remotely monitored on the patient and an emergency signal is transmitted to a central monitoring station by radio transmitter if the pulse rate or temperature suggests an emergency situation. Such systems are disclosed in U.S. Pat. No. 3,972,320 issued Aug. 3, 1976 to Kalman and U.S. Pat. No. 3,902,478 issued Sept. 2, 1975 to Konopasek et al. Such systems are not well adapted for use as emergency locators for sportsmen and the like, as they require setting of the pulse rate parameters by a physician, require connection of electrodes to the patient's skin to monitor the heart (as in Kalman) and are not suitably self sufficient in terms of battery power to be reliable in remote locations.